Kotlin & Java Developer

About the ProjectWe are looking for a Mid/ Senior Backend Engineer who enjoys building scalable services, collaborating across disciplines, and contributing to product development from concept to delivery for our e-commerce client. Work Mode: remote work with occasional onsite workshops and planning sessionsStart Date: ASAP, 12 months contractJob ResponsibilitiesDevelop and maintain backend services using Kotlin and JavaBuild and evolve applications based on Spring BootDesign, implement, and enhance microservice-based solutionsCreate and maintain reliable, high-quality APIs and backend componentsDevelop automated tests and ensure code quality standards are metDesign architecture for new functionalities and servicesImprove existing systems through performance, scalability, and maintainability enhancementsCollaborate closely with Product Managers, Data Analysts, and UX Designers to refine requirements and define technical solutionsContribute to engineering best practices and development standardsUtilize modern AI-powered development tools to increase productivity and code qualityExpectationsStrong proficiency in Kotlin and JavaHands-on experience with Spring BootProven background in designing and delivering microservicesExperience building, testing, and maintaining backend services and APIsAbility to design technical solutions and take ownership of implementation decisionsUnderstanding of software engineering best practices and clean code principlesExperience collaborating effectively with cross-functional product and business teamsPractical use of AI-assisted development tools such as GitHub Copilot, OpenCode, or similar agentic coding solutionsStrong communication skills and ability to work in an agile environmentBig plus if you have experience with frontend or mobile technologies (Web, iOS, or Android)We'll appreciate familiarity with MongoDB and Spring Data MongoDBA strong advantage if you have worked with Google Cloud Platform (GCP)English at B2+ level and fluent PolishWe offerOngoing support from a dedicated agent, taking care of your project continuity, client contact, necessary formalities, work comfort and developmentConsultant Development Program – advice on growth planning based on the latest trends and market needs in IT, including consultations with agents and growth mentorsAccess to 7N Learning & Development – a development and educational platform with webinars, a library of articles and industry reports, and regular invitations to one-time and recurring development events – technical, business, and lifestyleSpectacular integration events, both for you (e.g., annual Kick-Off trip, Christmas parties, or Summer Olympics sports events) and for your loved ones (e.g., family picnics, movie premieres)Professional development not only during the project – you can get involved in knowledge transfer to others within the 7N Services offering directed at 7N clientsRelationships and access to the knowledge of the most experienced IT experts in the market – the average professional tenure of our consultants in Poland is over 10 yearsA complete benefits package, including funding for medical care, life insurance, sports cards for you and your loved ones, as well as discounts in stores in Poland and abroadAbout 7NConstantly searching for projects, difficult rate negotiations, lack of development support – sounds familiar? At 7N, you gain not only stability of contracts but also the personal involvement of a dedicated agent who ensures your professional comfort and continuous access to development initiatives. Our mission is to provide stable and rewarding collaborations that drive your success as an IT expert and the success of our clients. We build long-lasting relationships based on Scandinavian values and 30 years of experience creating IT solutions for over 200 organizations.